<!--  CSS3 -->
<style>
.Links {
	float:left;
	width: 30%;
	background:green;
	height: 500px;
	border:solid 3px black;
	-moz-box-sizing:border-box;
	-webkit-box-sizing:border-box;
	box-sizing:border-box;
	padding-left:10px;
}
.Rechts {
	float:left;
	width: 70%;
	background:red;
	height: 500px;
	border:solid 3px black;
	-moz-box-sizing:border-box;
	-webkit-box-sizing:border-box;
	box-sizing:border-box;
	padding-left:10px;
}
</style>

<div class="container">
	<div class="Links">LINKS</div>
	<div class="Rechts">RECHTS</div>
</div>

<!-- CSS2 
<style>

#Links{
	width: 30%;
	height:500px;
	float:left;
	background:green;
}

#Links div{
	border: solid 1px;
	padding-left: 20px;
	height:500px;
}
#Rechts{
	width: 70%;
	height:500px;
	background:red;
	float:left;
}

#Rechts div{
	border: solid 1px;
	padding-left: 20px;
	height:500px;
}

</style>

<div id="Links">
	<div>Links</div>
</div>
<div id="Rechts">
	<div>Rechts</div>
</div>
-->